speculation about interfacing REST API from rexx

[Pablo-Fuentes]

Integrating modern REST APIs into mainframe workflows can significantly enhance agility, but many still hesitate due to perceived complexity. Is it truly that difficult to bridge legacy COBOL or REXX with cloud-native services? Could making REST calls from REXX be the key to unlocking a new era of mainframe adaptability and real-time data access?

[Anuj Dhawan]

Welcome to the forum Pablo-Fuentes, great to have you here!

It’s a great question — and in many cases, the perceived complexity is actually larger than the real effort involved. COBOL and REXX already have mature ways to invoke REST services today, whether through the z/OS Client Web Enablement Toolkit, Unix System Services (like using curl), or API-gateway–driven integration layers.The real difficulty isn’t making the REST call itself — that part is usually straightforward. The bigger challenges tend to be around TLS/cert management, JSON handling, timeouts, retries, and ensuring everything aligns with enterprise security and performance standards.Once those guardrails are in place, REST-enabling legacy workflows becomes just another I/O pattern, and it opens the door to real-time integrations and much more adaptive mainframe workflows.